Fan mounting



Sept. 8, 1942.

A. H. DAVIS, JR, ET AL 2,295,451

FAN MOUNTING Filed July 51, 1939 l N VEN TOR.-

By EDWIN O ARTINSON ATTORNEYS.

ARCHIBALD H. DAVIS JR.

Patented Sept. 8, 1942 -ITE STTES ATNT OFFICE FAN MOUNTING Application July 81, 1939, Serial No. 287,530

2 Claims.

The object of this invention is to provide a fan mounting that is light in weight, rugged and stiff, cheap to manufacture, and adaptable for mounting the assembled fan unit in a variety of ways.

A further object of the invention is to provide a fan mounting that can be set into a wall opening,'will seal the rough hole against air leakage, protect the fan from injury by loose particles of the wall material, and reduce the space taken out of'the room by the fan.

A further object of the invention is to provide a fanmounting which, though complete for use by itself, is adapted for use with an inlet or discharge duct or both, or which may even be used in 'positions where the fan acts as a booster in a duct line and is not supported on a Wall.

A further object of the invention is to provide a unitary fan mounting consisting of a single surface forming the liner, entrance ring, bolting surface, and sealing skirt.

The mounting of a disk fan must meet diverse requirements both mechanically and aerodynamically. Mechanically it must support the electric motor or the driving pulley and the fan. It must also provide for support of the entire fan assembly by the wall to which it must be attached. At times it is desirable to be able to support the fan independent of any wall. The fan mounting should also be as compact as possible, so as to reduce the distance which the fan driving equipment extends out into the room.

Aerodynamically the fan is considerably affected by air losses around the mounting, requiring a proper sealing of the mounting against the wall, and, by entrance losses which are reduced by a conical entrance approach.

Motor-driven disk fans are often installed in openings cut through existing walls, leaving a jagged over-size hole. It is convenient to have a fan mounting act as a liner to the hole, and to place the fan in the wall plane in order to reduce the distance from the Wall face to the back end of the motor. This has at times been accomplished by attaching the liner to a flap wall plate which lies against a wall face.

Since it has long been known that the efiiciency of a fan may be improved if there is an entrance a circle, this curve will function more smoothly if it is part of a logarithmic curve whose radius decreases from infinity toward the outer end of the entrance ring. When an entrance ring terminates with a flaring entrance opening, there will still be disturbance because air is drawn, in part, from the layer adjacent to a wall. As this layer flows up under an outwardly turned inlet opening, it must take a sharp 180 degree turn around the-edge of the inlet cone. This is undesirable. The invention provides for carrying the entrance ring outward into a transaxial plane, the rim of which walls considerably outside of a wall opening and lies parallel to the wall surface. To support the fan mounting in this position, a cylindrical reversely-extending skirt is provided. This outer skirt has a number of functions. Taken in connection with the flat rim of the entrance cone, it forms a circular stiffening angle. It also serves as a spacer, holding the inlet edge ofthe fan mounting, a fixed distance from the Wall surface. Its third function' is that of a seal, the edge of the skirt bearing against the wall at a point far enough away from the opening to prevent its being disturbed by the cutting of the hole through the wall. This cylindrical skirt also acts as a cover for the supporting bolts tending to exclude dirt and moisture. Furthermore it forms a smooth cylindrical surface which may act as a guide to support an inlet duct. The inlet duct may be slipped over, screwed on or otherwise attached directly to the skirt.

Figure 1 shows a vertical section of the invention as installed in an existing wall.

Figure 2 is a vertical elevation of an alternate installation in connection with a discharge duct and a thick wall.

Figure 3 is a vertical section of an alternate installation, showing the mounting in an installation having both an inlet and an outlet duct and no wall from which to support the fan.

Purely by way of illustration, the fan mounting has been shown as made of a single sheet which combines the functions of liner, inlet ring, bolting surface, skirt seal and skirt attachment ring, in one welded section.

The invention is not limited to any particular material or to the particular arrangement of the parts used illustratively.

I represents a fan mounting consisting of a liner 2, a tangent annular entrance ring 3, a flat transaxial area 4 supported by the skirt 5. Attachment bolts 6 pass through the surface 4 and the wall It] to be fastened by nut II or the like at the far side of the wall. When the nut l I is drawn up the skirt is pressed against wall I0, forming a seal preventing the flow of air through the space between the liner 2 and the edge of the hole in the Wall.

The mounting I carries braces l2 and [8 that support a base plate l3. Braces similar to l2 pass from the edge of the base plate l3 diagonally upward to ring 3 so that the three braces -one I2 and two l8 are well distributed around the rim, on which a motor I may be mounted in such manner that its shaft IE will pass along the axis of the mounting and the fan IE will come opposite the liner or throat 2.

It will be noted that the skirt 5 cooperates both to space the outer edge of the inlet ring from the wall, to support it thereon, to keep dirt and dust out from under the flaring inlet ring 3, and to stiffen the inlet acting as a circular angle ring.

Figure 2 shows how this same mounting readily permits a duct 20 to be slipped over the outside of a liner 2, without the necessity of making any seal between the duct and the wall. This illustration also shows how readily such a duct section may be used as an extension for the liner if the wall be a thick one. The motor and fan have been omitted to show brace 18 extending to the far side of ring 3.

Figure 3 shows the fan mounting employed in a different manner to support the fan and its driving motor in connection with both an inlet duct 22 and an outlet duct 20 where no wall is available against which the mounting can be supported. The air duct 22 fitting over the skirt 5 may be attached by screws or rivets 23. A frame of channels and angle irons is used to support the fan by suspending it from a ceiling beam 30. Two vertical angle iron hangers 3|, one behind the other, carry channels 32. Four bolts 6 draw that portion of the skirt 5 which is adjacent to the bolt up against the channels. As the inlet duct 22 seals against the skirt 5 and the outlet duct 20 against liner 2, it is not necessary that the fan mounting seal against the channels which take the place of the wall in supporting the fan mounting.

One experienced in the art will readily perceive other advantages in installation offered by the invention and will readily apply the principles shown to varied conditions.

We claim:

1. A fan mounting adapted for mounting a motor-driven fan in a duct line comprising an inlet duct, an outlet duct, and an annular ring of U-shaped cross section, one leg of the U adapted to support the inlet duct, the other leg of the U to support the discharge duct, the wall between said legs being tapered to serve as a flaring entrance ring, the U-shape serving both as an entrance ring for a fan and as means of securing a support rigid enough for mounting a spider that supports the fan concentric with the annular ring.

2. A ventilating fan adapted to be mounted in an opening in a supporting surface, comprising in combination, a short cylindrical ring of large diameter adapted to bear against the supporting surface, a funnel-shaped horn, whose outer rim is the diameter of the cylindrical ring and supported by it, and whose inner rim is part of a smaller cylinder extending into the hole in the supporting surface, a multibladed fan adapted to run in the throat of the horn, a motor whose axis is in the axis of the horn and whose shaft carries the fan, a supporting plate to which the motor is attached, spreading legs integral with the plate and the horn supporting the plate, said legs attached to the tapering surface of the horn, holes in the outer rim of the horn adapted for use in connection with bolts passing through the supporting wall, said cylindrical ring serving to stiffen the horn as the supporting bolts are drawn up.

ARCHIBALD H. DAVIS, JR. EDWIN O. MARTINSON. 

